EFFECT OF CHANNEL ORIENTATION OF LOCAL HEAT (MASS) TRANSFER DISTRIBUTIONS IN A ROTATING 2-PASS SQUARE CHANNEL WITH SMOOTH WALLS

Naphthalene sublimation experiments have been conducted to study the e ffects of channel orientation rotational Coriolis force, and a sharp t om, on the local heat (mass) transfer distributions in a two-pass squa re channel with a sharp turn and smooth walls, rotating about a perpen dicular axis. The test channel was oriented so that the direction of r otation was perpendicular to or at a 45 deg angle to the lending and t railing walls. The Reynolds number was kept at 5,500 and the rotation number ranged lip to 0.24. For the radial outward flow in the fil st s traight pass of the diagonally oriented channel, rotation-induced Cori olis force caused large monotonic spanwise variations of the local mas s transfer on both the leading and trailing walls, with the largest ma ss transfer along the outer edges of both walls. Rotation did not lowe r the spanwise average mass transfer on the leading avail and did not increase that on the trailing wall in the diagonally oriented channel as much as in the normally oriented channel. The combined effect of th e channel orientation, rotation, and the sharp turn caused large varia tions of the local mass transfer distributions on the walls at the sha rp turn and immediately downstream of the sharp turn. The velocity fie lds that were obtained with a finite difference control-volume-based c omputer program helped explain how rotation and channel orientation af fected the local mass transfer distributions in the rotating two-pass channel.